Flanging can bodies having prestretched circumferential edges



Nov. 15, 1966 E. .1. OBIDOWSKI FLANGING CAN BODIES HAVING FEE-STRETCHEDCIRCUMFERENTIAL EDGES Filed May 27, 1963 5 Sheets-Sheet 1 500v HEIGHT -1INVENTOR EDMOND J. OBmcuasm BY W %5 Nov. 15, 1966 E. .1. OBIDOWSKI3,285,212

FLANGING CAN BODIES HAVING PRE-STRETCHED CIRCUMFERENTIAL EDGES Filed May27, 1963 3 Sheets-Sheet 2 INVENTOR 44 I: & I4. EDMOND JOsmowsn 4o Fm...BY fig 45 m ATTORNEYS Nov, 15, 1966 E. J. OBIDOWSKI 3,285,212

FLANGING CAN BODIES HAVING PRE-STRETCHED CIRCUMFERENTIAL EDGES Filed May27, 1963 5 Sheets-Sheet 5 110 LO| 9'5 96 l. IF: 6. 5

9 104 .LOZ 94 TX 6-. I8

as M S INVENTOR 84 EDMOND J .Osmowsm ATTORNEYS United States Patent3,285,212 FLANGING CAN BODIES HAVING PRE- STRETCHED CIRCUMFERENTIALEDGES Edmond J. Obidowski, Nimes (Gard), France, assignor to ContinentalCan Company, Inc., New York, N.Y.,

a corporation of New York Filed May 27, 1963, Ser. No. 283,332 8 Claims.(Cl. 113-120) This invention relates generally to the art of makingmetal can bodies and primarily seeks to provide a novel method offorming a flange on a can body such that the flange does not crack orshear along an edge of the flange.

In the manufacture of can bodies, it is common practice to form the canbody either from a pre-cut blank or from a coil strip of thin highlytempered aluminum material or thin highly tempered tin-plated steel. Itis also known in this art to tin-plate the steel prior to a finalrolling operation to produce a very thin blank or strip. As a result ofthe rolling operation, the blank or strip becomes work hardened and lessductile. Thereafter, when a conventional flanging operation is performedto provide a can body with the usual flange for connecting a can end tothe can body, small ruptures or shear lines are likely to occur in theflange.

The ruptures or shear lines occur incidental to the outward bending ofthe ends of the can body because the perimeter of the end of the can isconsiderably enlarged and the metal at the bend is stretched on one sideand compressed on the other side thus producing shearing stresses whichcannot be resisted by the work hardened blank or strip.

It is the purpose of the present invention to provide a novel method offorming flanged can bodies in such a manner as to solve the problemreferred to above.

It is an object of this invention to provide a novel method of forming aflanged can body comprising the steps of providing a can body element,which element may be either a pre-cut blank or an elongated strip,prestretching at least one of opposite can body end forming portions ofthe can body element, and performing a flanging operation on each of theprestretched end forming portions of the resultant can body.

Another object of the invention is to provide a novel method of forminga flanged can body in which the prestretching is accomplished by acoining operation to produce an undulating wave in that portion of thecan body element from which the flange is made.

It is a further object of this invention to provide a novel method offorming a flanged can body comprising the steps of providing a can bodyelement, coining and scoring the can body element along opposite canbody end forming portions, and flanging the end portions of the canbody.

In accordance with the above set forth object, it is another object ofthis invention to first perform the coining operation and then toperform the scoring operation.

In accordance with the above set forth object, it is a further object ofthis invention to provide a modified method of forming a flanged canbody wherein the scoring operation is performed before the coiningoperation.

In accordance with the above set forth object, it is another object ofthis invention to provide a further modified method of forming a flangedcan body wherein the coining and scoring operations are performedsimultaneously.

A still further object of this invention is to provide a modified methodof forming flanged can bodies comprising the steps of providing anelement for forming a plurality of can bodies with the element havingopposed edges, forming a tubular member from the element, weldingtogether the opposed edges of the tubular member, circumferentiallycoining and scoring the tubular member at intervals corresponding to theheight of a can body, breaking the tubular member along the scoring toprovide a plurality of can bodies having opposite end portions andflanging each can body along each end portion thereof.

With the above and other objects in view which will hereinafter appear,the nature of the invention will be more clearly understood by referenceto the following detailed description, the appended claimed subjectmatter and the several views illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is a perspective view of a blank for forming a can body, theblank having a pair of edges which are to be joined together to form atubular can body and a pair of end portions for forming opposite endportions of the can body.

FIGURE 2 is a schematic elevational view and shows the blank beingdisposed between an upper and a lower pair of cooperating coining rollswith part of the blank already having been coined.

FIGURE 3 is a plan view of FIGURE 2 and illustrates that the coining 0fthe blank is limited to a small area along each of the opposite can bodyend forming portions of the blank.

FIGURE 4 is an enlarged cross-sectional fragmentary view taken on theline 4-4 of FIGURE 2 and shows the relative exemplary dimensions of theplate thickness and the amplitude of a wave or wrinkle produced by thecoining operation.

FIGURE 5 is a greatly enlarged fragmentary view of the lower right-handcorner of the coined portion of the blank shown in FIGURE 3.

FIGURE 6 is an elevation view of a can body which is formed from theblank shown in FIGURE 1, after the blank has been coined as shown inFIGURE 3, and shows that the periphery of the end portion of the can hasbeen enlarged with respect to the circumference of the machine forsimultaneously flanging two end portions of a can body and graphicallyillustrates how the undulating curl formed by the coining operation issmoothened during the flanging operation.

FIGURE 10 is a fragmentary enlarged cross-sectional view taken on theline 1010 of FIGURE 9 and shows a portion of an end portion of a canbody cooperating with a flanging die and flanging ring.

FIGURE 11 is a diagrammatic side elevational view of a welding line forforming a continuous tube from a metal strip and which tube is separatedinto can bodies, the welding line being provided with a pair ofcooperating scoring rolls for transversely scoring the strip at can bodyheight intervals and a pair of cooperating coining rolls fortransversely coining the scored strip in alignment with score linesformed thereon by the scoring rolls.

FIGURE 12 is a plan view of the welding line of FIGURE 11 and shows thescore dine extending completely across the strip and the coiningterminating at points slightly inwardly from the edges of the strip.

FIGURE 13 is a fragmentary cross-sectional view of the coining rolls incooperative engagement to impress the undulating curl into the canforming strip.

FIGURE 14 is an enlarged cross-sectional view on the line 14-14 ofFIGURE 13 and shows the strip being coined directly over the previouslyformed score line.

FIGURE 15 is a fragmentary diagrammatic view of a tube for making canbodies with portions broken away, and shows apparatus for making acircumferential score line in the tube and apparatus forcircumferentially coining the tube directly over a previously formedscore line.

FIGURE 16 is a diagrammatic elevation view illustrating one form of theinvention wherein the coining operation is performed prior to thescoring operation.

FIGURE 17 is a fragmentary view partly in section, taken on line 1717 ofFIGURE 16, and shows the scoring rolls inscribing a score line on thepreviously formed coined area.

FIGURE 18 is a diagrammatic elevation view and illustrates that form ofthe invention wherein the coining and scoring operations are performedsimultaneously.

FIGURE 19 is an enlarged fragmentary portion of the coiningand-scoringrolls shown in FIGURE 18.

FIGURE 20 is a fragmentary cross-sectional view taken on line 20-20 ofFIGURE 19 and shows the strip engaging portion of one of thecoining-and-scoring rolls.

Referring to the drawings in detail, and initially to FIGURES 1 to 10,there is shown a rectangular blank for forming a can body generallyindicated by the numeral 11. The blank 10 includes a top edge 12, abot-tom edge 13 parallel to the top edge 12, a first side edge 14, and asecond side edge which is parallel to the first side edge 14. The edges12 and 13 of the blank 10 are pre-cut to a measured length in accordancewith the circumferential length of the finished can body 11, land theedges 14 and 15 are pre-cu t to a measured length in accordance with theheight of the can body 11.

The blank 10 is fed between an upper coining roll 16 and a lower coiningroll 17 and is embossed with a plurality of undulating protuberancesalong the top edge 12 and the bottom edge 13 to prestretch the blank 10along .an area from which is fonmed a top flange 19 and a bottom flangefor the can body 11. Each of the coining rolls 16 and 17 is providedwith a plurality of cogs 21 separated ciroumiferentially by spaces 22.The cogs 21 on the coining roll 16 are designed for mating engagementwith the spaces 22 of the coining roll 17 and the cogs 21 on the coiningroll 17 are designed (for mating engagement with the spaces 22 in thecoining roll 16 to emboss the blank 10 with the protuberances 18. Eachof the cogs 21 and spaces 22 diminish in cross-sectional area inwardlyof the length of each roll 16 and 17 such that the amplitude of each ofthe protuberances 1-8 gradually diminishes into the planar body wallforming portion 23 of the can body 11.

The area of the blank 10 in which the protuberances 118 have been formedis prestretched such that the edges have been elongated and stresses inthis area of the blank 10 have been relieved. After the can body 11 hasbeen formed by joining the first side edge 14 and the second side edge15 by any known method to form a seam 24, the peripheral length of theedges 12 and 13 greater than the normal circumference of the side wall23. This prestretching of the flange forming portions of the blank 10eliminates the ruptures and shear lines which normally are likely to becaused during the flanging operation to be hereinafter described.

Attention is directed to FIGURE 9 which shows can bodies 11 havingprestretched top flange forming portions 19 and bottom flange formingportions 20 disposed for engagement with first flanging dies 30 on aleft flanging turret 31 and second flanging dies 3-2 on a right flangingturret 3 3. Each .flanging die 30 is provided with a flanging die slide34 and a flanging ring 35. Corresponding parts are also provided for theflanging dies 32, all of which are known in the can making art.

Prior to the present inventionit was the standard practice in the canmaking industry to form the required flanges on the can body bystretching the metal at the ends thereof. When the flanging dies movedinto the ends of the can body, shearing stresses were imposed thereonwhich caused rupturing or shear lines to occur at the edges as the metalof the end port-ions of the can body was stretched.

In accordance with the present invention, the bottom edge 13 and the topedge 12 of the can body 11 have been prestretched by the coiningoperation previously described such that when the dies 30 and 32 formthe flanges 3'6 and 37, as shown in FIGURE 9, it is only necessary thatthe flange forming portions 19 and 20 be forced to conform to the shapeof the dies 30 and 32. This allows the flanges 36 and 37 to form withvery little stretching which is required only to eliminate or iron outthe protuberances caused during the prestretching operation and therebyproduces a can body 11 having the desired flanges which are required forthe double seaming operation which is performed in connecting a can endto the can body.

A modified form of the invention is illustrated in FIG- URES 11 through14 from which it will become apparent that the .present invention isreadily adaptable for use in making cans from an elongated strip of canbody forming material. FIGURES 11 and 12 show a strip 40 being fed froma coil between cooperating scoring rolls 41 and 42 for forming scorelines 43 completely across the strip 40. As the strip 40 continues tothe right, as shown in FIGURES 11 and 12, each score line 43 becomesdisposed between an upper coining roll 44 and a lower coining roll 45and is engagd by cogs 46 of the roll 44 and cogs 47 of the roll 45 suchvthat the strip 40 is embossed with a series of protuberances 50 whichextend transversely of the strip 40. As shown in FIGURES 12 and 13, theportion of the strip 40 which is embossed with the protuberances 50 endsslightly short of the marginal edges 50 and 51 so that the embossedprotuberances 50 will not interfere with the forming of a welded seam53, which joins the edges 51 and 52, at a welding station, generallyindicated by the numeral 54, for forming the strip 40 into an elongatedtubular member 55. Forge rolls 56 are provided at the welding station 54to insure a proper seam 53.

A modified form of the invention is illustrated in FIGURES 16 and 17from which it will be apparent that the coining operation is performedprior to the scoring operation. A can body forming strip 60 is fed (froma source not shown) between an upper coining roll 61 and a lower coiningroll 62. The coining rolls 61 and 62 are similar to the previouslydescribed coining rolls 44 and 45 and are provided with mating cogs 63and 64 respectively. The embossed portion of the strip 60 is then fedbetween cooperating scoring rollers 65 and 66. As can be seen in FIGURES16 and 17, the scoring roll 65 is provided with a scoring blade 67 forproducing a score line 68 transversely of the strip 60 along thepreviously coined portion thereof.

The scoring blade 67, as is shown in FIGURE 17, is designed for matingengagement with the protuberances 69 formed in the strip 60 by thecoining drums 61 and 62. The score line 68 extends completely across thestrip 60 but the protuberances 69 of the embossed portion of the stripterminate short of the marginal edge of the strip 60 so as not tointerfere with the welding operation which is to be performed in themanner described with reference to FIGURES 11 and 12.

In FIGURES 18 through 20, there is illustrated another form of theinvention wherein the coining operation and scoring operation areperformed simultaneously. A can body forming strip 80 is fed from asource not shown between cooperating combined scoring and coining rolls81 and 82 which are provided with mating cogs 83 and 84, respectively.In addition to the cogs 83, the roll 81 is also provided with a scoringblade 85. The scoring blade 85 corresponds to the general configurationof the cogs 83. As shown in FIGURE 20, the scoring blade 85 terminatesat a marginal edge 86 of the roll 81 such that the strip 80 will bescored completely transversely of its length, while the roll 81 has cogs83 which do not extend to the marginal edge 86 but terminate inwardlytherefrom. Thus, the strip 80 is provided with a coined portion 87 andhas a score line 88 therein.

After the strip 60 and the strip 80 have been coined and scored, asabove described, the strips are shaped into tubular form, such as thetubular member 55 as shown in FIGURE 12, and a welding operation isperformed to provide the resultant tubular members with a welded seam,such as the seam 53. The tubular members are then broken along theirrespective score lines so as to provide a plurality of can bodies. Eachof the can bodies formed in this manner is provided with flange formingportions at the opposite edges thereof, which portions have beenprestretched by the coining operation such that flanges formed by theapparatus shown in FIGURE 9,

and described above, will not have ruptures or shear lines therein.

Another modified form of the invention is illustrated in FIGURE 15 fromwhich it Will be apparent that the scoring and coining operation may beperformed after the tubular can body forming member has been Welded. Asshown, a tubular can body forming member 90 having a welded seam 91 ismoving to the right as indicated by the arrow 92. A scoring device 93 isreciprocated along the path of travel of the tubular member 90, by meansnot shown, to produce longitudinally spaced circumferential score lines94 in the tubular member 90. The scoring device 93 includes a scoringblade 95 which is mounted on an annular block 96 which is integral withan annular gear 97. The block 96 and the gear 97 have a passageway 98centrally therethrough to permit passage of the tubular member 90. Thescoring blade 95, block 96 and gear 97 are rotated about thelongitudinal axis of the tubular member 90 by a drive pinion 99 which isconnected to a drive shaft 100 which is driven by a source of power, notshown.

A plurality of circumferential score lines 94- are formed at measuredintervals along the length of the tubular member 90 such that thetubular member 90 may be subsequently broken along the score lines toprovide a plurality of can bodies. Prior to the breaking operation, thetubular member 90 is coined circumferentially along the score lines 94by a coining apparatus, generally indicated by the numeral 101. Thecoining apparatus 101 includes a coining roll 102 mounted on an annularblock 103 which is integral with an annular gear 104. The coiningapparatus 101 is reciprocated along the path of travel of the tubularmember 90 by a form of reciprocating means not shown and the coiningroll 102, block 103 and gear 104 are rotated by a pinion 105 which is 6connected to a shaft 106 which is driven by a source of power not shown.

The coining apparatus 101 is further provided with a back-up coiningroll 108 which is eccentrically mounted on a shaft 109 which ispositioned interiorly of the tubular member 90. The shaft 109 may besupported in cantilever fashion by supporting means, not shown, whichare disposed above the strip which forms the tubular member just priorto the welding station (such as the welding station 54 in FIGURE 12)which provides the seam 91 for the tubular member 90.

The scoring apparatus 93 and the coining apparatus 101 may beoperationally mounted independent of each other or it may be preferableto interconnect these mechanisms by a connecting rod which is adjustableto space the scoring blade and the coining rolls 102 and 108 at variousdistances which correspond to the height of the desired can body. Aretracting mechanism 110 is provided for retracting the scoring blade 95out of engagement with the tubular member 90 prior to leftward movementof the scoring apparatus 93 upon completion of the cutting of score line94. The coining apparatus 101 is also provided with a retractingmechanism 111 for retracting the coining ro'll 102 out of contact withthe tubular member 90 prior to the leftward movement of the embossingapparatus 101 after the coining roll 102 has circurn-ferentiallyembossed the tubular member 90.

The tubular member 90 is subsequently broken along the plurality ofscore lines 94 to provide a plurality of can bodies which have beenprestretched at their edges along areas which are flange formingportions. The can bodies are subsequently operated upon by the mechanismshown in FIGURE 9 such that can end receiving flanges are formed on thecan bodies without any ruptures or shear lines being formed therein.

While preferred forms and alrangements of parts have been shown inillustrating the invention, and preferred methods of prestretching theflange forming portions of the can bodies have been disclosed in detailherein, it is to be understood that variations in the forms andarrangement of parts and in the various method steps may be providedwithout departing from. the scope of the invention as defined in theappended claimed subject matter.

I claim:

1. The method of forming a plurality of flanged can bodies from a stripof sheet plate having a length sufficient to provide a plurality of canbodies comprising the steps of prestretching said sheet plate along atleast one area thereof transversely of said length which areacorresponds to a portion of the area laying adjacent an end of acompleted can body, forming said sheet plate into a plurality of canbodies and flanging at least one end of each can body.

2. A method of forming a flanged can body from a rectangular body blankhaving opposed edges and opposed ends comprising the steps ofprestretching the body blank along at least one of the opposed ends,joining the body blank along said oppose-d edges thereof and normal tosaid opposed ends to form a seamed tubular can body, and forming aflange along each prestretched end.

3. The method of forming a flanged can body comprising the steps ofproviding a can body element, prestretching and forming at least one ofopposite can body end forming portions of said can body element bycoining the can body element to stretch the metal thereof in an areawhich lies within a larger area from which a flange is to be formed andsimultaneously positively pressing the stretched area of metal into theform of an undulating wave, forming the can body element into a seamedtubular can body and finally flanging each prestretched wave shaped endforming portion of the r sultant can body.

4. The method of forming a plurality of can bodies from a strip of sheetplate having a length suflicient to provide a plurality of can bodies,said method compris- 7 ing the steps of coining and scoring said stripof sheet plate transversely of the length thereof, forming said strip ofsheet plate into a plurality of can bodies each having a coined areadisposed along a can body end portion, and forming a flange from thecoined area of each of said plurality of can bodies.

'5. The method as defined in claim 4 wherein the step of coining thestrip of sheet plate is performed before the step of scoring the stripof sheet plate.

6. The method as defined in claim 4 wherein the step of scoring thestrip of sheet plate is performed before the step of coining the stripof sheet plate.

'7. The method as defined in claim 4 wherein the step of coining thestrip of sheet plate and the step of scoring the strip of sheet plateare performed substantially simultaneou sly.

8. The method of forming a plurality of can bodies from a strip of sheetplate having a length sufficient to provide a plurality of can bodies,said method comprising the steps of coining and scoring said strip ofsheet 8 plate transversely of the length thereof at intervalscorresponding substantially to can body height intervals, forming saidstrip of sheet plate intoa tube, and separating said tube into aplurality of can bodies.

References Cited by the Examiner UNITED STATES PATENTS 901,963 10/1908Hardie 113l20 1,915,318 6/1933 Hothersall 113l20 2,259,498 10/1941Taylor 22076 2,350,824 6/1944 Rojo 113-12O 2,616,588 11/ 1952 Heinle220--76 2,742,872 4/ 1956 Geersten 1137 3,053,209 9/1962 Smith et al1137 3,088,624 5/ 1963 Kinghorn et a1 22054 CHARLES W. LANHAM, PrimaryExaminer.

EARLE DRUMMOND, Examiner.

G. E. LOWRANCE, R. D. GREFE, Assistant Examiners.

1. THE METHOD OF FORMING A PLURALITY OF FLANGE CAN BODIES FROM A STRIPOF SHEET PLATE HAVING A LENGTH SUFFICIENT TO PROVIDE A PLURALITY OF CANBODIES COMPRISING THE STEPS OF PRESTRETCHING SAID SHEET PLATE ALONG ATLEAST ONE AREA THEREOF TRANSVERSELY OF SAID LENGTH WHICH AREA CORRSPONDSTO A PORTION OF THE AREA LAYING ADJACENT ON END OF A COMPLETE CAN BODY,FORMING SAID SHEET PLATE INTO A PLURALITY OF CAN BODIES AND FLANGING ATLEAST ONE END OF EACH CAN BODY.